FIELD OF THE INVENTION
This invention relates to oil well cleaning apparatus, and more particularly, in one embodiment to a reamer tool for scraping and removing paraffin, scale, ice and other accumulations from the inside surfaces of oil well tubing and casing. In an alternative embodiment the tool can be modified to loosen tubing in an oil or gas well. The reamer tool of this invention is designed to operate in cooperation with a wire line fitted with a swivel joint, and with a load application means such as one or more spanner jars, for alternately applying a repetitive impact load to the tool and sequentially repositioning the tool for further load application.
The problem of restricted flow of hydrocarbons in oil wells due to the accumulation of paraffin and other deposits on the inside wall of the tubing is one of great concern in the oil field. Paraffin accumulation sometimes occurs in a relatively short period of time, and can form a tough, semi-solid deposit which severely restricts the flow of fluid in the tubing. Accumulation thickness and character vary with the type and quantity of oil and hydrocarbon fluid produced, and frequently causes severe stress in pumping apparatus and equipment, with resulting equipment failure or low operating efficiency. Typically, the accumulation of paraffin deposits in oil well production tubing occurs at a point where the hydrostatic pressures and temperatures create favorable conditions for precipitation of solid paraffin from the oil. Other deposits such as rust, scale and ice must frequently be removed from production tubing and casing, particularly in corrosive environments, and in the case of ice, in regions characterized by prolonged low temperature.